Which situation is an example of an observational study?

a.) Having a randomly selected group of students take a pen and paper test and comparing the results with another randomly selected group of students who took the same test on the computer?

b.) Polling voters about their favorite candidates in upcoming elections.

c.) Recording the reaction time of participants in a study who were asked to press a button as soon as they see a certain picture on a screen.

d.) Asking kids in a kindergarten classroom about the average number of pieces of fruit they eat each day.

Answer:

  see below

Step-by-step explanation:

If suffices to look at the last term. It must simplify to 4/(3w²), so the exponents of z must match in numerator and denominator, and the ratio of constants must reduce to 4/3.

The exponents of z have the right values in choices B and D, but the ratio of constants only matches in choice D. Looking at the rest of choice D, we see that we can factor 6w²z² from both numerator and denominator, then factor 2 from the remaining numerator to make it match the desired form.

  [tex]\dfrac{(12w^2z^4-24w^2z^2)}{18w^4z^2}=\dfrac{6w^2z^2}{6w^2z^2}\cdot\dfrac{2z^2-4}{3w^2}=\dfrac{2(z^2-2)}{3w^2}[/tex]

Answer: C 25/9

Step-by-step explanation:

Answer:

y = -x + 4

perp: m = 1

y + 4 = x - 3

y = x - 7

Step-by-step explanation:

Answer:6 = 6 represents a true statement because 6 is always equal to 6. When graphed on a coordinate plane, this equation would result in a straight line at y = 6, which means that every point on the line corresponds to a solution of the equation. Since the line extends infinitely in both directions, there are infinitely many solutions to this equation.

Step-by-step explanation:

Answer:

Similar polygon

Step-by-step explanation:

Answer:-.6666666667x +6

Step-by-step explanation:

I have a school calculator

Answer:

-2/3 is the slope

Step-by-step explanation:

Slope = y2 - y1/x2 - x1

= 10 - 4/-6 - 3

= 6/-9

=-2/3

Answer:

C.x/(x+5)(x-2)

Step-by-step explanation:

Answer:

b

Step-by-step explanation:

Make an x and y table, and pick any values to plug in for x in the equation.

I will use the numbers from -2 to 2

Now plug in the values you picked for x into the equation to find its y-value

x = -2

y = 3x - 1   Plug in -2 for x

y = 3(-2) - 1

y = -6 - 1

y = -7

x = -1

y = 3x - 1

y = 3(-1) - 1

y = -3 - 1

y = -4                

Do the same for the rest of the numbers, and graph each point and draw a line connecting them.

Answer:

f(x) = 1/2x^2 – 4x + 5  (the third option)

Step-by-step explanation:

I looked it up on a graphing calculator.

The quadratic function that has a minimum located at (4, -3) is:

[tex]f(x) = (1/2)*x^2 - 4x + 5[/tex]

All the options are quadratic functions, so we need to find the one with a leading coefficient positive, which also has a vertex at (4, -3).

The 3 ones with positive leading coefficients are:

[tex]f(x) = (1/2)*x^2 + 4x -11[/tex]

[tex]f(x) = (1/2)*x^2 - 4x + 5[/tex]

[tex]f(x) = 2x^2 - 16x + 35[/tex]

The vertex of the first one is at:

[tex]x = -4/(2*1/2) = -4[/tex]

The x-value of the vertex must be x = 4, so we can discard this.

For the second quadratic function the x-value of the vertex is:

[tex]x = -(-4)/(2*1/2) = 4[/tex]

Then the y-value of the vertex is:

[tex]f(4) = (1/2)*4^2 - 4*4 + 5 = -3[/tex]

Then the vertex is at (4, -3), so this is the correct option.

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Answer:

rest set option

Step-by-step explanation:

Answer:

there are 2 groups

Step-by-step explanation: 14 x 2 = 28

Answer:

Complementary angles

Step-by-step explanation:

Complementary angles add up to 90 degrees

Answer:

2000 ml

Step-by-step explanation:

Given: Sarai pours all the liquid from a full small beaker into a  larger beaker.

           The liquid fills the large beaker to 15% of its capacity.

            The small beaker holds 300 ml.

Lets assume capacity of large beaker to hold be "x".

As given, Sarai pours all the liquid from a full small beaker into a larger beaker

∴ [tex]15\% \times x= 300\ ml[/tex]

⇒ [tex]0.15x= 300[/tex]

Dividing both side by 0.15

⇒[tex]x= \frac{300}{0.15}[/tex]

∴ [tex]x= 2000\ ml[/tex]

Hence, the large beaker can hold 2000 ml of liquid.

Answer:

The value of the expression is 4.

Step-by-step explanation:

Consider the provided information.

We have given that:

[tex]\dfrac{2\dfrac{1}{2} }{\dfrac{1}{8} } =20[/tex]

Now we need to find the value of:

[tex]\dfrac{2\dfrac{1}{2} }{\dfrac{5}{8} } =?[/tex]

Consider the provided fact:

[tex]\dfrac{2\dfrac{1}{2} }{\dfrac{1}{8} } =20[/tex]

Multiply [tex]\frac{1}{5}[/tex] both sides.

[tex]\dfrac{1}{5}\times \dfrac{2\dfrac{1}{2} }{\dfrac{1}{8} } =20\times\dfrac{1}{5}[/tex]

[tex]\dfrac{1\times2\dfrac{1}{2} }{5\times\dfrac{1}{8} } =20\times\dfrac{1}{5}[/tex]

[tex]\dfrac{2\dfrac{1}{2} }{\dfrac{5}{8} } =4[/tex]

Hence, the value of the expression is 4.

Answer:

[tex]\frac{8h}{\sqrt{2}} + 16h[/tex]

Step-by-step explanation:

First we need to compute the side length as a function of h

So x be the side length of the right isosceles triangle, in Pythagorean formula we have

[tex]x^2 + x^2 = h^2[/tex]

[tex]2x^2 = h^2[/tex]

[tex]x = \frac{h}{\sqrt{2}}[/tex]

The cost for the legs is

[tex]C_l = 4*2x = \frac{8h}{\sqrt{2}}[/tex]

The cost for the hypotenuse is

[tex]C_h = 16h[/tex]

So the total cost in term of h is

[tex]C = C_l + C_h = \frac{8h}{\sqrt{2}} + 16h[/tex]

The total cost C of construction as a function of h is C =  16 / h +  8√2 / h

The pen is in the shape of an isosceles right angle. This means one of the

angle is 90 degrees and 2 sides of the triangle are equal and the base angles

are equal too.

Using pythagora's theorem

Therefore,

x² + x² = h²

2x² = h²

x² = h² / 2

x = √h²/ √2 = h/√2

cost of the legs = 4 / h/√2 + 4 / h /√2 = 8√2 / h

cost of the hypotenuse = 16 / h

Total cost = 16 / h +  8√2 / h

C =  16 / h +  8√2 / h

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Answer:

Step-by-step explanation:

First, start off by solving for the slope using this formula:

[tex]\frac{y_{2} -y_{1} }{x_{2}-x_{1} }[/tex]

Then, plug in the values: [tex]\frac{0-(-3)}{7.5-0}[/tex]

Solve the equation: [tex]\frac{3}{7.5}[/tex]

That's your slope.

Then plug in one of the coordinates given in the problem for x and y and solve this equation:

y=[tex]\frac{3}{7.5}[/tex]x+b

Hope that helped!!! :)

The x-Intercepts of the line 2x - 4y = -12 is -6 and the y-intercept is 3.

To identify the x and y intercepts of the line, we set one variable to zero and solve the equation for the other variable.

For the x-intercept, we set y=0 and solve for x in the equation: 2x - 4(0) = -12, hence x = -6.

For the y-intercept, set x=0 and solve for y in the equation: 2(0) - 4y = -12, hence y = 3.

Therefore, the x-intercept is -6 and the y-intercept is 3

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Answer:

$34

Step-by-step explanation:

So he earns $24 per week (ima just say p/w to make it shorter) meaning he earned around $216 in total. To get to $25 p/w, you have to get $250 in total from the 10 weeks. So $250 - $216 = $34.

⭐ Answered by Foxzy0⭐

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Answer:

The number 1 is not necessary when expressing powers of one. For example, you needn't write "5" as [tex]5^{1}[/tex].

Step-by-step explanation:

The number 1 is written when it is part of a larger number, as it is significant. It is not necessary to write leading zeros. In scientific notation, trailing zeros are excluded, and the number is written in a form where only non-zero digits appear before the decimal.

Understanding when to write the number 1 and when it's not needed depends on the context in mathematics, especially when dealing with significant figures and scientific notation. Generally, all non-zero numbers are considered significant (rule 1), which means that when a value like 1 is part of a larger number, it contributes to the meaning of that number. However, leading zeros do not count as significant (rule 3).

In the case of multiplication by units, like converting from kilograms to grams, we utilize the concept of multiplying by the number 1 to affect the units without changing the value. For example 0.7 kg can be multiplied by 1000/1 (1000 g / 1 kg) to convert to grams. This is because 1000/1 is equal to 1000, indicating multiplication by one does not change the value.

When expressing numbers in scientific notation, it's important to include the non-zero digits only before the decimal point, excluding any trailing zeros. Thus, 1,500,000 would be written as 1.5 x 106, with the power indicating the necessary number of decimal point movements to place it after the first significant digit.

The answer is in the graph picture

The zeros of the function f(x) = (x - 1)(x - 7) are 1 and 7

The function is given as:

f(x) = (x - 1)(x - 7)

Set the function to 0.

So, we have:

f(x) = (x - 1)(x - 7) = 0

This gives

(x - 1)(x - 7) = 0

Split

(x - 1) = 0 or (x - 7) = 0

Remove brackets

x - 1 = 0 or x - 7 = 0

Solve for x

x = 1 or x = 7

Hence, the zeros of the function are 1 and 7

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Answer:

A' (-4,0)

Step-by-step explanation:

The complete question is

If the triangle on the grid below is translated by using the rule (x, y) right-arrow (x minus 2, y + 2), what will be the coordinates of A prime? On a coordinate plane, triangle A B C has points A(negative 2, negative 2), B(negative 2, negative 4), C(2, negative 4)

we know that

The rule of the translation is

(x,y) -----> (x-2,y+2)

The coordinates of point A (-2,-2)

Applying the rule of the translation to coordinate A

A (-2,-2) ----- A' (-2-2,-2+2)

A (-2,-2) ----- A' (-4,0)

Answer:

The answer is A on edge

Step-by-step explanation:

Answer:

C.

Step-by-step explanation:

2 times 2 times 2 times 5 = 40

The prime factorization of 40 is 2 times 2 times 2 times 5, which can be written as 2^3 * 5. So, option C, "2 times 2 times 2 times 5," is the correct prime factorization of 40.

The prime factorization of the number 40 is 2^3 * 5. To arrive at this factorization, we break down 40 into its prime factors. We start by dividing 40 by the smallest prime number, 2. Since 40 is even, it can be divided by 2 evenly, resulting in 20. We continue this process until we can no longer divide by 2, which leaves us with 20. Now, we try to divide 20 by the next smallest prime, which is also 2. This division gives us 10. Once again, we divide by 2, and we are left with 5. Since 5 is a prime number, we cannot further divide it. Therefore, we have prime factorized 40 as 2 * 2 * 2 * 5, which can be expressed as 2^3 * 5, where the exponent 3 indicates that we have three 2s multiplied together, and the 5 is the prime factor on its own.

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Answer:

X-Intercept is -45. (Answer would be (-45,0))

Step-by-step explanation:

You can use Desmos which is a graphing calculator to figure out the answer. Plug the equation into Desmos and it will show you a line and where the x-intercept is. And boom, you got your answer.

Answer:

x=6

Step-by-step explanation:

Let the number be x

Then 4 times a number divided by 3 is 5 more than that number divided by 2 gives the equation:

[tex] \frac{4x}{3} = \frac{x}{2} + 5[/tex]

Multiply through by the LCD, which is 6.

[tex] 6 \times \frac{4x}{3} = 6 \times \frac{x}{2} + 5 \times 6[/tex]

Cancel out to obtain:

[tex] 2 \times 4x =3 \times x + 30[/tex]

[tex]8x = 3x + 30[/tex]

Group similar terms

[tex]8x - 3x = 30[/tex]

Simplify the LHS

[tex]5x = 30[/tex]

Divide both sides by 5 to get:

[tex]x = 6[/tex]

Answer:

2x + 13 = 3x - 2

Step-by-step explanation:

This should be the answer

Answer:

its 2

Step-by-step explanation:

Answer:

25 minutes is how long Carter played

Step-by-step explanation:

To find out how many minutes Carter plays, multiply 40 minutes by 5/8, which results in 25 minutes of playtime.

To determine the number of minutes Carter plays in a basketball game, which is 40 minutes long, when he plays 5/8 of the game, we use multiplication. We multiply the total game time by the fraction of the game played:

Steps to calculate:

Therefore, Carter plays for 25 minutes of the basketball game.